Homogeneous alkaline detergents and method of producing same



Jan. 3,1939. 1;; A, HALL v 2,142,871

HOMOGENEOUS ALKALINE DETERGENTS AND METHOD OF PRODUCING-SAME Filed June 14, 1937 F151- 1 F152. F153, F154.

'v Jan. 3,

nomoamaons AND PATENT orries DETEBGENTS ALKALINE METHOD PRODUCING SAME Lloyd A. Ball, Chicago, 111., assignor to The Grifiith laboratories iinois ma, a corporation or 11- Application June 14, 1931, Serial No. 148,018

The present invention relates to improvements in alkaline compounds and more particularly in homogeneous alkaline detergents comprising or including phosphate compounds.

In the preparation and use of alkaline detergents and particularly those consisting partly or entirely of trisodium phosphate, dimculty has been encountered because, among other reasons, of the instability of such products in respect of their water content. Normal trisodium phosphate crystals have a very high water content,

part of which is readily given up on changes in moisture contentof the atmosphere and hence this material, as such, is uneconomical and produces dissatisfaction in use because of unsightli ness, changes in condition 0! thematerial in opened packages and changes in its solubility, rate of solution, and strength with changes in water content. when prepared in the form of 4 hydrates of lower water content orthe anhydrous material, alone or in admixture with other alkalies, oxidizing agents and the like, the resuiting-products are likewise unstable. sometimes deliquescing and becoming wetin the; package or causing reactions with other constituents of the detergent mixture; and sometimes causing caking or, on attempts to put the material in solution, agglomerating and iorming masses which are not readily penetrated by the water 39 and hence not readily dissolved. Attempts have been made to correct these difllculties by varl- 45 respect of its water content. As a result, the

product in accordance with the present invention. even when in finely powdered form, is in all respects uniform throughout in characterand properties and may be permitted to remain in open 50 packages without coking or becoming wet or unsightly, and may be employed in detergent mixtures. particularly with oxidizing agents,'hypo-' chlorites, perborates, and the like without causin: reaction resulting from instability 0: water a content.

(c1, 87-5) I c In accordance with the present invention, trisodium phosphate and borax are dissolved partly or completely in water, and the resulting mixture heated for removal of water and to leave a minor proportion thereof, less than that required to 5 satisfy the normal requirements of the constltu ents for water of crystallization and generally less than 25% and preferably in the range from 5 to 15%. The trisodium phosphate compound employedmay be either anhydrous, the mono i hydrate, the normal crystallinedodecahydrate or some intermediate hydrated form. In carrying out'theprocess for the production of the product according to the present invention, in the reduction of the water content 01' the solution or par- 15 'tial solution of the mixed constituents to a point below that reuuire'dior the satisfaction of the normal hydration process in forming crystalline compounds 01' the constituent substances, a remarkable phenomenon occurs in that in the com- 20 petition for water, there is apparently a complete dehydration of the phosphate constituent and, in fact, a tendency to convert the phosphate in the direction 01' the anhydrous pyro-compound, not withstanding the presence of some proportions 5 oi water to the extent hereinbefore indicated, with the formation of a solid solution of the borate constituent in the phosphate constituent. The change in structurepi the constituents of themixture as the result of the process of the present invention is clearly shown from an inspection oi. the characteristic x-ray diflractlon patterns of the resulting products;

It is now well understood and established that such substances are distinguishable by the arrangement oi the atoms and molecules making up the crystal and by the spacings between them;

and that on; passing an x-ray beam through the substance and permitting the diffracted beams to set one photographic him or plate, a pattern is 40 \secured which is determined by the arrangement of the crystal lattice planes and which is characteristic of the substance. By passing a monochromatic beam of x-rays' through a compacted powder mass of the substance and recording the 'diiiracted rays upon a photographic emulsionsuri'ace. lithe latter is disposed in the form of a cylindricafsection with its axis perpendicular to the incident beam, the diflracted beams will be recorded as lines spaced from the position or the 5g incident beam. The resulting patterns or traces are characteristic and their positions are deter: mined by the spacings oi the lattice planes of the definite crystalline substance or substances mak-. ing up themoiecules oi the material under in'- u vestigation (Applied X-Rays" by George L. Clark, 2d ed., 1932, New York, pages 226 to 228 and 252, 253). Hydrated complexes, with water as a constituent part of the molecule, are thus distinguishable, as are solid solutions, in which the characteristic pattern of one of the constituents persists with but'slight displacement of the positions of the lines due to the displacement of the lattic planes of the dominant constituent on intermolecular penetration of the other. The products of the present invention are shown by the similarity of the characteristic patterns to those of ignited anhydrous trisodium phosphate to be borate-phosphate compositions in which the borate constituent is present in the form of a solid solution in the anhydrous phosphate constituent. When these products are examined by X-ray analysis, their diffraction patterns show a substantial suppression or in some cases complete disappearance of the characteristic lines and spacings of borax, presenting those of anhydrous phosphates of the character resulting from the ignition of sodium phosphates with in some cases a slight displacement or doubling.

The invention will be more fully understood from the following description thereof, illustrated by the accompanying drawing, in which:

Figure 1 represents diagrammatically the characteristic X-ray diffraction pattern (recorded on a cylindrical film cassette) of anhydrous sodium phosphate ignited for 30 seconds;

Fig. 2 shows a characteristic pattern secured in a similar manner from a composition produced in accordance with the present invention; and

Figs. 3 and 4 show characteristic patterns produced in a similar manner from other products prepared in accordance with the present invention. Referring more particularly to the drawing, as stated hereinbefore, Fig. 1 shows diagrammatically the principal lines and spacings of the characteristic pattern produced one cylindrical film by difl'raction of the K mono-chromatic X- ray beam from a copper anticathode by compacted powdered anhydrous sodium phosphate which has been ignited at white heat for 30 seconds. Certain of the stronger or more intense lines of the pattern have been indicated respectively by'the numerals i to l6 inclusive.

In the drawing the representations of the characteristic patterns are diagrammatic, and the width and intensity of the lines being, however, indicated to the extent possible in such drawing.

Figs. 2, 3 and 4 "represent diagrammatically.- characteristie patterns secured on X-ray analysis of products formed in accordance with the present invention, and will be described more fully in connection therewith. l

.In carrying out the present inventionhthe trisodium phosphate and borax in the desired proportions, with the constituents such as a sodium carbonate compound if desired, are mixed with water to form a slurry or to completely dissolve the mixture. The mixturemay then be heated and agitated to eflect partial or complete solution, and is then suitably heated to drive ofl water, leaving in the mixture less than s'uillcient water to satisfy the requirements of the constituents oi. the mixture for forming normally crystalline compounds, and preferably not more than25%.

' The heating may be efiected in open pans, driving of! water until sputtering takes plac, a temperature of 107 to 115 C. beingreached, the mix-.

ture solidifying on cooling to a hard mass which may then, if desired, be heated at. say, 130-140 0.

01 the line 1b.

, A product made in a similar manner by adto further reduce its moisture content, and may 7 be ground to any desired degree of fineness; or it may be efl'ected on a drum, for example, on chromium-plated drying drums at a temperature 01 300 to 350 F.

The proportions of phosphate and borate constituents may vary considerably, the borate ranging from one-half to one-fourth of the solid constituents of the mixture. The phosphate constituent may be the normal crystalline trisodium phosphate, the monohydrate or the anhydrous compound. Varying proportions of a sodium carbonate compound such as sodium carbonate or sodium sesquicarbonate may be present, ranging up to 25 to 33% of the solid constituents of the mixture.

The following specific examples are illustrative:

3 parts-by weight of monohydrated trisodium phosphate are mixed with 1 part by weight of borax and 2 parts by weight of water in one case 'and 4 parts in another, the admixture heated to effect partial or complete solution depending upon the proportion of water present, and evaporated to a water content of from 7 to 10%. In

shown the characteristic diffraction pattern of.

these products secured under the conditions referred to in connection with the patterns of Fig. 1, previously described. The pattern does not show lines and spacings characteristic of borax. It does, however, show lines substantially similar in position and spacing to those of Fig. 1 with some slight variations and apparent omissions due to variations in intensity of lines in the record of the pattern, with but slight displacement, the respective lines being designated by the numerals lb, 2b, 311, lb, 5b, lb, 8b, H11, and I3!) and corresponding in position respectively with a slight displacement to the lines in the pattern of Fig. 1 bearing the same numbers but withoutvthe sumxes. An additional line b appears faintly on Fig. 2 that is not shown on Fig. 1, as but slight indicatibn of its presence appears on the original record. It is to be noted, also, that the'lines llb, displaced somewhat with respect to the position of the line ll of Fig. 1, are doublev in this pattern, and there is an inclination of doubling mixing} parts by weight of monohydrated trisodium phosphate, 1 part by weight of borax and 3 parts by weight of water. heating the mixture to eflect solution and evaporating the resulting solution to about 5% water content, permitting'the mass to solidify and grinding it to a powder, gave a product which recorded a characteristic X-ray diflractionpattem substantially.

identical with 'those previously referred to and illustrated in Fig. 2. In this product the molecular proportions are about 4.2 of phosphate to 1 of-borax.

-Using normal crystalline trisodium. phosphate in-varyi'ng proportions,with borax and water to eflect partial or complete solution and reducing the .water content '0! the mixture to below and preferablybelo'w 15%, the resulting product has a characteristic X-ray diflraction pattern illustrated in Fig. 3 which, it will be noted, is substantially similar in respect 'of most oi the lines and their spacings to that of 76 out the sufilxes) in Fig. 1, and lines lie and 200 to lines lib and 20b of Fig. 2.

For example, 1 part of normal crystalline tri'- sodium phosphate was, mixed with 1 part of borax (or about equimolecular proportions) and 2 parts by weight of water, the mixture heated to effect solution and then heated in an open pan to, remove 'water until the mixture had a low water content amounting to about 12.98%-

on the final product and congealed to a hard' mass on cooling. The product was then powdered. By proceeding similarly with a mixture containing initially 3 parts of normal crystalline trisodium phosphate and 1 part of borax, with 4 parts of water, a product containing about 7.4% water was secured and each of these products, on X-ray analysis, gave the characteristic diffraction pattern shown in Fig. 3.

The compound produced as Just described appears to be similar in sc lar as the nature of the phosphate constituent is concerned, to that which is produced with the'monohydrated trisodium phosphate and borax when the former is in higher proportions than in the examples pre-' viously given. For examplewhen 1 part of monohydrated trisodium phosphate and 1 part by weight of borax with 2 parts by weight of water were heated to effect solution, and the solution dehydrated to about 12% water content, and

the resulting mixture hardened on cool ng, the.

powdered product gave, on X-ray analysis, a

diffraction pattern substantially identical with that of Fig. 3.

' The persistence of the numerous lines and their spacings in the pattems illustrated in Figs. 3 and 4"o'ver'the range of proportions'of the constitu ents of the products yielding them clearly indicates their presence in the form of a solid v solution in which the anhydrous phosphate con-- stituent is present as the dominant constituent. The presence of sodium carbonate or sodium sesquicarbonate in varying proportions up to 25 4 to 33% of the mixture does not appear to substantially alter the action which takes place.

Thus, on mixing 2 parts of normal crystalline trisodium phosphate. '1 part of borax,1 part of anhydrous sodium carbonate and 4 parts of water, heating the mixture to effect solution and subsequently evaporating the water from the mixture,

a product was secured having a water content of about 12.7% and which, on X-ray, analysis, failed to show distinctly either the characteristic patternsof borax or sodium carbonate, but did record a pattern as shown in Fig. 4, in which a 'number of the same characteristic lines and spacings are apparent as in. Fig. 3. as indicated at Id, 211, 3d, 4d, 5d,' 1d, 8d, lid, Nd and 20d-in .15 Fig. 4, with additional less prominent lines probably due to the carbonate constituent. In this product the molecular proportions are about 2 of phosphate to 1 of borate to about 3.6 of car bohate. Substantially similar results were se- 7 cured on using initially 1 part of monohydrated trisodium phosphate, 1 part of borax and 1 part of sodium carbonate with 3 parts of water; and also in another case .by using 2 parts of'normal trisodium phosphate, 1 part'ot borax, 1 part or sodium sesquicarbonate and inens of water.

in respect of their water content.

used therein. They are likewise excellent cleanproportion of borax varying from about oneof the pattern obtained from borax. e

The borate-phosphate products of the present invention have been found to be markedly stable finely powdered, they are completely uniform and homogeneous throughout and they do not tend to dryxout excessively and likewise they do not tend to become wet, deliquesce, or cake. They dissolve readily and rapidly and do not tend to 16 agglomerate and form difficultly soluble masses when poured or thrown into water to form solutions.

'lI'he products of *the, present invention are suitable for use as water softeners and are effective in improving the lathering qualities of soaps and the permanence of the lathers formed. They do not injuriously affect thehands and skin of users, as they are free from caustic alkali. They are excellentfletergents or cleaners vfor use in dairies,.bakeries, kitchens and the like, as they have but slight corrosive action upon tin and other metals (other than aluminum) commonly ers for stone, cement,'metal work and the like.

By reason of the stability of their water content, the products of the present invention are also well adapted to form detergent mixtures or compositions with other substances, particularly those which are readily aflected or decomposed by moisture and hence cannot-ordinarily be usedwith phosphates, carbonates and other detergent alkalies which ordinarily yield a part of their Jl'lOlStllIC content readily or which tend to deliquesce or become wet in humid atmosphere. 40

Although the present invention has been described in connection with the details of specific examples embodying the same, it is. noti'ntended that these details shall be regarded as limitations on the scope of the invention. except in so 45 far as included in the accompanying claims.

I claim:

1. The method of producing a homogeneous stable alkaline detergent product containing sodium borate and phosphate compounds in solid 50 phosphate and borax in the presence of a quantity of water greater than that in the final product and su'fficient to form at least a slurry. the

55 hall to about one-fourth-of the solid constituents. thereby driving off water and reducing the water content of the mixture to 5 to 25% thereof, whereby a stable solid solution is formed having an X-ray diffraction pattern including lines and 60 spacings characteristic of ignited anhydrous sodium phosphate.

' 2. The method of producing a homogeneous stable alkaline detergent product, containing sodium borate and phosphatecompoundsin solid solution which comprises heating a trisodium phosphate and borax inthe presence of a quantity of water suilicient to-dissolve thernixture, the proportion of borax varyingfrom about onehalf to aboutv one-fourth of the solid constituents, thereby driving off water, and reducing the water content of the mixture to 5 to 25% thereof, thereby forming crystalline compounds, whereby a stable solid sol .tion is formedhaving an X-ray diflraction pattern including lines and spacings Even when 10 characteristic of ignited anhydrous sodium phosphate.

3. The method of producing a homogeneous, stable alkaline detergent product containing sodium borate and phosphate compounds in solid solution which comprises heating a trisodium phosphate and borax in the presence of a quantity' of water sufllcient to at least form a slurry, the proportion of borax varying from about onehalf to about one-fourth of the solid constituents, thereby driving off water and reducing the proportion of water to to 15% of the mixture, whereby a stable solid solution is formed having an X-ray difiraction pattern including lines and spacings characteristic of ignited anhydrous sodium phosphate.

4. The method of producing a homogeneous stable alkaline detergent product containing sodium borate and phosphate compounds in solid solution which comprises heating a trisodium phosphate, borax and a sodium carbonate compound in the presence of a quantity of water suilicient to at least form a slurry, the proportion of borax varying from about one-half to about one-fourth of the solid constituents and the proportion of sodium carbonate compound being not in excess 0. about one-third of the solid constituents, thereby driving of! water and reducing the water content of the mixture to 5 to 25% thereof, whereby a stable solid solution is formed having an X-ray diffraction pattern including lines and spacings characteristic of ignited anhydrous sodium phosphate.

5. The method oi producing a homogeneous stable alkaline detergent product containing sodium borate and phosphate compounds in solid solution which comprises heating a trisodium phosphate and borax in the presence of a quantity of water sumcient to at least form a slurry, the proportion of the trisodium phosphate being from 1 to 3 times the proportion of the borax, thereby driving oil! water and reducing the water content of the mixture to 5 to 15% thereof, whereby a stablesolid solution is formed having an X-ray diffraction pattern including lines and spacings characteristic oi. ignited anhydrous sodium phosphate.

6. The method of producing a stable, alkaline detergent product containing sodium borate and phosphate compounds in solid solution which comprises heating a trisodium phosphate, a sodium carbonate compound and borax in the presence oi a quantity oi. water sufilcient to at least form a slurry, the proportion of said constituents being from 1 to 2 parts of the trisodium phosphate to l'part or the borax and 1 part of the sodium carbonate compound, driving of! water from the mixture and reducing the water content of the mixture to'5 to 5% thereof, whereby a stable solid solution is formed having an X-ray diflraction pattern including lines and spacings characteristic of ignited anhydrous sodium phosphate.

7. A stable, homogeneous, alkaline boratephosphate detergent product containing 5 to 15% of water and comprising in solid solution at least partly dehydratedcrystalline compounds of trisodium phosphate and borax in which the arcasn initial proportion of the phosphate compound is from 1 to 3 times that of the borax compound,

and said product having an X-ray diflraction pattern including lines and spacings characteristic of ignited anhydrous sodium phosphate.

8. A stable, homogeneous, alkaline boratephosphate detergent product containing water in proportions vary from about 5 up to 25% and comprising in solid solution at least partly dehydrated crystalline compounds of trisodium phosphate and borax with sodium carbonate in which the carbonate is present in proportions not in excess of about one-third of the trisodium phosphate and borax and in which the initial proportion of the phosphate compound is from 1 to 3 times 'that of the borax compound, and said product having an X-ray diflraction pattern including lines and spacings characteristic of ignited anhydrous sodium phosphate.

9. A stable, homogeneous, alkaline boratephosphate detergent product containing 5 to 25% 01 water and comprising in solid solution at least partly dehydrated crystalline compounds of trisodium phosphate and borax lnwhich the initial proportion 01 the phosphate compound is from 1' to 3 times that of the borax compound.

istic of ignited anhydrous sodium phosphate and being substantially free of lines characteristic of the borax compound.

10. A stable, homogeneous, alkaline boratephosphate detergent product comprising in solid solution at least partly dehydrated crystalline compounds or trisodium phosphate and borax with sodium carbonate, the proportions of said constituents being from 1 to 3 parts oi. the tri sodium phosphate compound to 1 part of the borax and 1 part of the sodium carbonate compound, said product containing in stable form 5. to 15% of water and having an X- ray diifraction pattern including lines and spacings characteristic of ignited anhydrous sodium phosphate.

11. A stable, homogeneous, alkaline beratephosphate detergent comprising in solid solution at least partly dehydrated crystalline compounds of trisodium phosphate and borax'in which the initial proportion oi the phosphate compound is from 2 to 3 times that of the borax compound, the said product containing in stable form from 5 to 15% of water and having an X-ray diii'raction pattern including lines and spacings characteristic of ignited anhydrous sodium phosphate.

12. A stable, homogeneous, alkaline detergent.

product containing water in proportions varying from 5 up to 25% and comprising in solid solution at least partly dehydrated crystalline compounds of trisodium phosphate and borax with sodium -sesquicarbonate, the initial proportions of said LIDYDA.HAI.L.' 

